Unnamed (Knight Island, half a mile north of the head of Hogan Bay)

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite; native copper; pyrrhotite
Gangue minerals chert

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale A-3
Latitude 60.2159
Longitude -147.7622
Nearby scientific data Find additional scientific data near this location
Location and accuracy The prospect is located in the westernmost drainage north of the head of Hogan Bay at an elevation of 1,150 feet. It is in the SW1/4 section 32, T. 2 N., R. 10 E., of the Seward Meridian. This is location S-29 of Jansons and others (1984). This location is accurate to within a quarter of a mile.

Geologic setting

Geologic description

The workings on the prospect consists of an 8-foot- by 20-foot-long open cut at an elevation of 1,150 feet and a 6-foot- by 10-foot-long open cut at 1,200 feet elevation. The larger cut exposes greenstone containing a mineralized zone that averages 2 feet thick. The zone is conformable with the flow layers of the greenstone. Sulfides consist of as much as 2 percent chalcopyrite and 4 percent pyrrhotite. Total sulfide content of the cut is about 1 percent (Kurtak and Jeske, 1986). The smaller cut exposes of chert interbedded with greenstone and contains as much as 1 percent total sulfide. Native copper occurs in the lower cut (Kurtak and Jeske, 1986). Bedrock in this area is Orca Group of early Tertiary age (Nelson and others, 1985).
Geologic map unit (-147.764247238668, 60.2153290163342)
Mineral deposit model Cyprus massive sulfide (Cox and Singer, 1986; model 24a)
Mineral deposit model number 24a
Age of mineralization Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age.

Production and reserves

Workings or exploration Development on the prospect consists of an 8-foot- by 20-foot-long open cut at an elevation of 1,150 feet and a 6-foot- by 10-foot-long open cut at 1,200 feet elevation (Kurtak and Jeske, 1986). The smaller open cut is 900 feet southwest of the larger one. Three discontinuous chip samples from both open cuts contained between 120 ppm and 1.4 percent copper and from 0.0 to 8.2 ppm silver (Kurtak and Jeske, 1986).
Indication of production None

References